What is the difference between probation and parole?

Furthermore, the standards of proof differ in the two methods. Probation[37 Cal.App.3d 521] and parole are granted in the hope and expectation that the conditional release, under supervision, will better serve to rehabilitate a defendant than would supervised incarceration. The court, or the paroling authority, need not wait until the defendant proves, by new acts of criminality, that the hope and expectation were unfounded. Acts short of criminality, or evidence which leaves a criminal violation still uncertain, may well, in the judgment of the court or authority, indicate that the hoped for rehabilitation is on the road to complete failure and that a more restrictive process is required both to protect society and to assist the defendant toward ultimate rehabilitation. (Cf. People v. Hayko (1970) 7 Cal.App.3d 604, 86 Cal.Rptr 726.)